Which combination is part of the MONA protocol for acute myocardial infarction management?

• A. Morphine, Oxygen, Nitro, Aspirin
• B. Oxygen, Nitro, Aspirin, Beta-blocker
• C. Morphine, Oxygen, Nitro, Anticoagulant
• D. Morphine, Oxygen, Nitro, Antihistamine

Answer: (A)

MONA is the initial approach to suspected acute myocardial infarction, focusing on quick relief of ischemia and stabilization by analgesia, oxygen if needed, a vasodilator to reduce heart work, and an antiplatelet to limit clot propagation. Morphine eases pain and anxiety, which lowers sympathetic drive and reduces myocardial oxygen demand. Oxygen is used to improve oxygen delivery to the ischemic myocardium, especially if the patient is hypoxemic. Nitroglycerin dilates veins to decrease preload (and afterload), lowering ventricular wall stress and oxygen demand while helping to improve coronary perfusion. Aspirin irreversibly inhibits platelet aggregation by blocking thromboxane A2, helping prevent further clot growth. The other drug types listed—beta-blockers, anticoagulants, or antihistamines—aren’t part of the MONA quartet, though beta-blockers and anticoagulants have roles in broader ACS management and antihistamines are not relevant here.